Memory Mangement Problem in 5.1-RELEASE

Daniel C. Sobral dcs at
Fri Jul 25 04:44:31 PDT 2003

Jeremy Messenger wrote:
> Well, the 5.0, old -CURRENT and 4.8 have never touch the swap, until 
> 5.1- CURRENT. My system has 256mb ram and it's always touch swap now. If 
> I compile some stuff, sometime it will get around 300mb swap. Current, I 
> only have Gnome 2.3.x and Opera running, so what my top looks like this:
> Mem: 85M Active, 29M Inact, 51M Wired, 4496K Cache, 35M Buf, 73M Free
> Swap: 512M Total, 79M Used, 433M Free, 15% Inuse
> But, I will remove the Gnome System Monitor applet, then reboot and see 
> how it goes for the whole afternoon.

People, swap is just a backing store for idle data. If you have 79 Mb 
that isn't getting used, what would you prefer: to keep it swap-backed 
so you can throw the pages out on demand, or *wait* until your system is 
heavily loaded to put the pages on the swap?

Anyway, placing data on the swap is not a problem. What is a problem is 
what some call "swapping": reading and writing to the swap all the time.

Start a "vmstat 1" and see if pi and po have non-zero values constantly. 
If not, then your system is _not_ wasting time writing and reading to 
the disk.

(btw, unless you have disk activity, writing data to the swap does not 
impact on performance either)

Daniel C. Sobral                   (8-DCS)
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         dcs at

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